Theories of how humans came to be so ecologically dominant increasingly centre on the adaptive abilities of human culture and its capacity for cumulative change and high-fidelity transmission. Here we revisit this hypothesis by comparing human culture with animal cultures and cases of epigenetic inheritance and parental effects. We first conclude that cumulative change and high transmission fidelity are not unique to human culture as previously thought, and so they are unlikely to explain its adaptive qualities. We then evaluate the evidence for seven alternative explanations: the inheritance of acquired characters, the pathways of inheritance, the non-random generation of variation, the scope of heritable variation, effects on organismal fitness, effects on genetic fitness and effects on evolutionary dynamics. From these, we identify the open-ended scope of human cultural variation as a key, but generally neglected, phenomenon. We end by articulating a hypothesis for the cognitive basis of this open-endedness.

关于人类如何成为生态主导地位的理论越来越集中在人类文化的适应能力及其累积变化和高保真传播的能力上。在这里，我们通过比较人类培养物和动物培养物以及表观遗传和亲本效应的案例来重新审视这一假设。我们首先得出结论，累积变化和高传播保真度并不像以前认为的那样是人类文化所独有的，因此它们不太可能解释其适应性。然后，我们评估了七种替代解释的证据：获得性状的遗传、遗传途径、变异的非随机产生、可遗传变异的范围、对生物体适应性的影响、对遗传适应性的影响和对进化动力学的影响。从这些中，我们确定了人类文化差异的开放性范围是一个关键但通常被忽视的现象。最后，我们阐明了这种开放式的认知基础的假设。